A study to obtain a higher diploma at the College of Medicine, Basra University, discussed the level of cancer antigen 125 concentration in pregnant women during normal pregnancy and preeclampsia cases in the blood of the student Hala Majed Khanjar. The research aims to evaluate the relationship between the concentration of CAA 125 serum in the blood serum in normal pregnancy compared to preeclampsia and to study the importance of this antigen in determining the extent of toxicity of preeclampsia. The research concluded that the average level of cancer antigen 125 serum in women with preeclampsia is much greater than that of preeclampsia. In normal pregnancy, the research recommended its use as an indicator to evaluate pregnancy outcomes.